What is the future state of evolutionary architecture? As teams become more familiar with the ideas and practices, they will subsume them into business as usual and start using these ideas to build new capabilities, such as data-driven development.
Much work must be done around the more difficult kinds of fitness functions, but progress is already occurring as organizations solve problems and open source many of their solutions. In the early days of agility, people lamented that some problems were just too hard to automate, but intrepid developers kept chipping away and now entire data centers have succumbed to automation. For instance, Netflix has made tremendous innovations in conceptualizing and building tools like the Simian Army, supporting holistic continuous fitness functions (but not yet calling them that).
There are a couple of promising areas.
Fitness Functions Using AI
Gradually, large open source artificial intelligence frameworks are becoming available for regular projects. As developers learn to utilize these tools to support software development, we envision fitness functions based on AI that look for anomalous behavior. Credit card companies already apply heuristics such as flagging near-simultaneous transactions in different parts of the world; architects can start to build investigatory tools to look for odd behaviors in architecture.
A practice common in many functional programming communities gaining wider acceptance is the idea of generative testing. Traditional unit tests include assertions of correct outcomes within each test case. However, with generative testing, developers run a large number of tests and capture the outcomes then use statistical analysis on the results to look for anomalies. For example, consider the mundane case of boundary checking ranges of numbers. Traditional unit tests check the known places where numbers break (negatives, rolling over numerical sizes, and so on) but are immune to unanticipated edge cases. Generative tests check every possible value and report on edge cases that break.